Climate Services for Heat-Risk Management at the Dakar 2026 Youth Olympic Games: A Competition-Zone Assessment Using WBGT and UTCI

Heat stress has become a major concern for the organization of outdoor sporting events under a warming climate, yet climatological decision-support frameworks remain scarce for African Olympic venues. This study aims to characterize climatological heat risk during the Dakar 2026 Youth Olympic Games (YOG) and to develop an operational framework to support competition scheduling. Hourly ERA5 reanalysis data (1991–2025), restricted to the official Games period (31 October–13 November), were used to compute the Wet-Bulb Globe Temperature (WBGT) and the Universal Thermal Climate Index (UTCI). Long-term trends, climatological diurnal cycles, and hourly probabilities of exceeding operational heat-stress thresholds were analyzed across the three competition zones (Dakar, Diamniadio, and Saly). Heat stress increased significantly over the study period, with WBGT P90 trends ranging from +0.33 to +0.47 °C decade−1, while UTCI P90 also increased significantly in Dakar and Diamniadio. A persistent spatial gradient (Saly > Diamniadio > Dakar) was identified, and the highest heat-stress levels consistently occurred between 11:00 and 17:00, peaking around 14:00–15:00. Integrating WBGT and UTCI within a hierarchical decision-support framework showed that early morning (before 09:00) and evening (after 19:00) provide the most favorable periods for outdoor competitions, whereas midday requires precautionary measures or schedule adjustments, particularly in Saly and Diamniadio. These findings demonstrate that climatological information can be translated into actionable climate services supporting heat-risk management for major sporting events. Although intended for long-term planning, the proposed framework should be complemented by real-time weather forecasts during the Games to support operational decision making.